Recently, much progress has been made in increasing the brightness of light emitting diodes (LEDs). As a result, LEDs have become sufficiently bright and inexpensive, to serve as a light source in for example lighting arrangements such as lamps with adjustable color. By mixing differently colored LEDs any number of colors can be generated, e.g. white. An adjustable color lighting system is typically constructed by using a number of primary colors, and in one example, the three primaries red, green and blue are used. The color of the generated light is determined by the LEDs that are used, as well as by the mixing ratios. To generate “white”, all three LEDs have to be turned on. By using LEDs it is possible to decrease the energy consumption, a requirement which is well in line with the current environmental trend.
As a consequence of having the possibility to provide bright light of different colors, a number of different illumination devices have been proposed where a user is giving the option to change the color to suit the current psychological mood or for creating a specific illumination design. Philips LivingColors is a commercially available example of such an illumination device.
In relation to the Philips LivingColors illumination device, there is provided a user interface in the form of a remote control for allowing the user to change the color and the intensity of light emitted by the illumination device. However, in relation to larger illumination system comprising a plurality of illumination devices there is a desire to provide a more comprehensive user interface that allows for overall control of the different illumination devices for creating and adjusting the common illumination pattern created jointly by the different illumination devices.
An example of such a user interface for controlling light attributes of a lighting interaction system is disclosed in WO 2008/120127 assigned to the applicant and fully incorporated by reference in its entirety. More specifically WO 2008/120127 relates to a user interface comprising a pointer that may be used by a user for pointing to one of a plurality of indicators corresponding to lighting settings relating to for example time of day, description of a natural light condition, season of year, weather, and phase of a moon. Accordingly, by means of the user interface it may be possible to control the lighting interaction system such that a jointly created illumination pattern provided by a plurality of light sources of the lighting interaction system mimicking natural light.
However, even though the lighting interaction system of WO 2008/120127 provides a common user interface for a plurality of light sources, it may be desirable to provide even more intuitively adapted control of such a lighting interaction system, for example related to the feedback provided to the user during operation of the user interface.